C taper question

BurntFingers

Well-known member
They're called reverse taper. Does that mean you need to wire them 'backwards' for them to follow the usual logic of clockwise = more?

I thought it was just a different taper with a confusing name but I don't get to see C taper pots much. Now I'm designing a thing based loosely off the dod 250. I used an a1m pot for gain which is more like an on/off switch. Seeing the original used a C taper pot got me thinking and confused.

0 is still 0, 10 is still 10 right? Just how you get there is different according to the taper? Or is 0 = 10 and 10 = 0.

I've not had enough coffee for this.
 
The C indicates reverse action (imagine opening a gate valve).
Tapered means that the majority of the change in resistance is in a more "audibly familiar" distribution.
Linear is a 1:1 ratio.

Hope that helps!
 
Correct me if I'm wrong, but I think this graph helps. Purple being C taper. It's the "reverse" of A taper.


View attachment 11025
Yeah that's what I was visualising. I think calling it inverse rather than reverse is more logical. Reverse makes people think it's going to work backwards as in clockwise is 10, ccw is 0, which I don't think is the case (when wired typically, I understand you can make any pot 'backwards').
 
I always look at the halfway point to try and understand taper to me its more apparent what actually happens with the resistance you can see reverse or inverse rises much quicker at the start to the midway point

At the mid point linear is almost exactly half in reality it isn't you'll always get at least a few ohms with the pot fully CCW

Log 20% and Reverse log over 80%

The absolute best way to understand it is get your meter on a pot and turn it to see what happens I always forget when using a pot as a variable resistor which way resistance goes depending on what lugs I jumper so I'll grab a pot stick a clip on lugs 1 and 2 turn it and see if it increases or decreases if it increases I know if I jumper 2 and 3 it'll decrease

I'm at work don't have a pot handy and I've forgotten again even though I've done it zillions of times haha
 
Yeah that's what I was visualising. I think calling it inverse rather than reverse is more logical. Reverse makes people think it's going to work backwards as in clockwise is 10, ccw is 0, which I don't think is the case (when wired typically, I understand you can make any pot 'backwards').
I agree, inverse is a better term.
@mjh36 nailed it !
 
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